Can the application of sports nutrition
principles enhance academic performance?
It is now widely accepted that achieving potential in sport is not just about training hard. Healthy eating and making the right food choices is inextricably linked to better performance in sport, enabling practitioners train, compete and recover stronger and faster. Active young people need good nutrition to support basic growth and development as well as additional nutrient-rich calories to fuel their sport. A balanced and varied diet, with particular emphasis on slow-release carbohydrates, lean protein, unsaturated fats and adequate hydration not only provides sustained energy, but concentration and focus. The principles of sports nutrition can be adapted to the suit the diet of less active pupils; nourishing the body with a healthy, unprocessed, nutrient-rich diet will fuel the brain for effective learning, optimising the pupil’s ability to engage in the classroom and therefore achieve his or her potential.
The human brain is a highly metabolically active tissue that depends on a constant supply of blood glucose to meet its energy needs. Composed principally of fat and water, the brain’s billions of cells, or neurons, require fats, protein and complex carbohydrates as well as micronutrients, for instance B vitamins such as thiamin, riboflavin, niacin and pantothetic acid and minerals such as magnesium, iron and manganese. Energy, generated from food, regulates the growth and change of the cells. There have been many studies over the past ten years on the influence of diet on mental function in young people. For instance, recent research by the Human Appetite Research Unit at the University of Leeds shows that habitual breakfast eating and school breakfast programmes have a positive effect on children’s academic performance, with the clearest effects being measured on the mathematical and arithmetic grades of undernourished children. According to the report, children who skip breakfast have more difficulty focussing on classroom tasks and concentrating in class, which is apparent in both well and undernourished children and children from deprived backgrounds.(1)
Most sports practitioners will agree that carbohydrate, converted into blood glucose, or glycogen, and used for energy or stored in the liver and muscle, is the principle source of energy for their sport. Glycogen stored in the muscle is used to fuel the muscles; glycogen stored in the liver is used to maintain steady blood glucose levels for the body and brain.
Using the concept of the glycaemic index, (G.I.) a measurement which measures the speed at which glucose is digested into the bloodstream, we can manipulate the carbohydrates we eat to sustain our energy levels, concentration and focus.
Students who consume high G.I. foods for breakfast, for instance, sugary cereals, sugary fizzy drinks, doughnuts, which are rapidly digested into the bloodstream, will have a burst of energy followed by a mid-morning slump. This can lead to fidgeting, lack of concentration, headaches or drowsiness. The student will then often consume more sugary foods to boost their energy, thus continuing the cycle.
Meals and snacks containing complex, lower G.I. carbohydrates, such as whole grain cereals, oats, wholemeal bread, fruits and starchy vegetables are richer in nutrients, containing more fibre, which slows down the absorption of the carbohydrate, as well as micronutrients vital to healthy brain function, such as B vitamins and vitamin E. Commonly eaten by sports practitioners, these carbohydrates release glucose into the bloodstream more gradually and will therefore provide more sustained levels of energy, concentration and focus.
The speed at which carbohydrate is absorbed into the bloodstream can be further reduced if eaten with protein. In sport, a 4:1 carbohydrate to protein ratio is often cited as the ideal combination for sustaining energy and fuelling the muscles for growth, repair and recovery. For instance, a peanut butter sandwich on wholemeal bread, or a banana and a natural yoghurt. This can be applied to the classroom too. As well as sustaining concentration levels, protein provides amino acids, building blocks that are used to support structures in neurons. Good sources of protein are found in lean meat such as chicken or turkey, fish, eggs, pulses, beans and grains, as well as raw nuts and seeds.
Fat is an important nutrient for children, particularly those who practice sport on a regular basis. Children need fat to provide essential fatty acids for healthy growth and development, to fuel the muscles, to transport vitamins and proteins around the body, to carry fat-soluble vitamins such as vitamins A, D, E and K, to promote healthy skin and nerve function and to manufacture important hormones. However, the majority of fats they eat should come from unsaturated fats, found in avocados, oily fish, nuts and seeds and cold-pressed vegetable oils, rather than saturated fats, the fats found in processed meats, cream, and hydrogenated vegetable oils (transfats, found in processed cakes and pastries).
Numerous studies have been carried out over the past ten years around the world (ii)(iii) which provide evidence that a diet rich in omega-3 fatty acids (found in oily fish, avocados, nuts, seeds) can play a role in improving mood and brain development. The brain consists largely of fatty membranes. Fats help maintain flexible, dynamic membranes which can transmit and receive information. Fernando Gómez-Pinilla, a UCLA professor of neurosurgery and physiological science has analyzed more than 160 studies about food's affect on the brain. He states "Food is like a pharmaceutical compound that affects the brain ... Diet, exercise and sleep have the potential to alter our brain health and mental function. This raises the exciting possibility that changes in diet are a viable strategy for enhancing cognitive abilities, protecting the brain from damage and counteracting the effects of aging. Synapses in the brain connect neurons and provide critical functions; much learning and memory occurs at the synapses. Omega-3 fatty acids support synaptic plasticity and seem to positively affect the expression of several molecules related to learning and memory that are found on synapses. Omega-3 fatty acids are essential for normal brain function. Dietary deficiency of omega-3 fatty acids in humans has been associated with increased risk of several mental disorders, including attention-deficit disorder, dyslexia, dementia, depression, bipolar disorder and schizophrenia .... A deficiency of omega-3 fatty acids in rodents results in impaired learning and memory .... Children who had increased amounts of omega-3 fatty acids performed better in school, in reading and in spelling and had fewer behavioral problems”. Gómez-Pinilla goes on to say that while supplements may have a place sometimes, it is normally best for children to get their omega-3s from their diet.
Ann-Charlotte Granholm of the Medical University of South Carolina in Charleston, studied rats (iv) on a high trans-fat diet and found they developed learning difficulties. Granholm compared rats on a diet high in unsaturated fat with those on a high transfat diet. When the animals were required to remember the position of hidden platforms in a maze, the animals on the trans-fat diet learned more slowly and made more errors, especially with more difficult tasks. This is one example of evidence that a child eating mostly processed foods with trans and saturated fats will build a different brain to a child who eats a balanced diet, including fish, nuts, eggs and lean meats.
Several studies (v)(vi) have shown that cognitive function, especially in terms of concentration and attention, is improved with good hydration throughout the day, and this has led to better provision of drinking water in many schools in both the US and the UK.
The British Nutrition Foundation recommends that children and adults should drink 6-8 glasses of fluid per day, preferably keeping fluid levels topped up throughout the course of the day. This does not have to be just water; fruit juice, milk, tea, coffee also count. Teenage boys, in particular, need more fluid than girls. There are no agreed recommended daily intake levels in the UK specifically for teenagers, but recommendations from the US National Academies Food and Nutrition Board suggest that 9-13 year old girls should drink 1.6 litres per day, and boys should drink 1.8 litres per day, 14-18 year old girls should drink 1.8 litres per day, and boys should drink 2.6 litres per day. Active children, as with active adults, should then drink in addition to this during hot weather and before, during and after physical activity.
Good hydration is key for children who want to perform to the best of their ability, both mentally and physically. Children are at more risk of dehydration because they have immature thirst mechanisms. Even mild dehydration can have physiological consequences. A simple loss of just 1% of body weight (for a 40kg child, thats just 400ml) can start to decrease performance. Dehydration can lead to fatigue, dizziness, impaired concentration and reduced cognitive abilities. Children in classrooms can be given encouraged to keep a water bottle at their desks to sip throughout the day to achieve the recommended intake of 8 glasses a day, with 4 consumed during the school day.
The food we serve our children will influence their eating habits, and consequently their health for the rest of their lives. Childhood, according to the British Heart Foundation, is when the pernicious seed of heart disease and obesity is sown. Encourage young people to be active and to enjoy and understand the benefits of eating the right foods and you’ll not only teach them good habits for life, you’ll promote healthy growth and development of both body and brain. Just as what, when and how a child eats is the foundation to good performance in sport, it can also play an important role in enhancing concentration and better academic attainment in school pupils.
i) Katie Adolphus*, Clare L. Lawton and Louise Dye "The effects of breakfast on behavior and academic performance in children and adolescents", Human Appetite Research Unit, Institute of Psychological Sciences, University of Leeds.
For more information, see: http://www.frontiersin.org/Human_Neuroscience/10.3389/fnhum.2013.00425/full#h1
ii) University of California – Los Angeles “Scientists Learn How Food Affects the Brain: Omega 3 Especially important”. Science Daily 11 July 2008. www.sciencedaily.com/2008/07/080709161922.htm
iii) Durham Fish oil trials
iv) Science Daily http://www.sciencedaily.com/releases/2008/07/080709161922
v) Anci KE, Constant F and Rosenberg IH (2006) Hydration and Cognitive Function in Children, Nutrition Reviews 64: 457-464
vi) Edmonds CJ and Burford D (2009) Should children drink more water? The effects of drinking water on cognition in children. Appetite 52:776-9
N is for Nutrition